From eeb8461e36c99fdf2d058751be924a2aab215005 Mon Sep 17 00:00:00 2001 From: Yishai Hadas Date: Tue, 28 Jan 2014 13:40:15 +0200 Subject: IB: Refactor umem to use linear SG table This patch refactors the IB core umem code and vendor drivers to use a linear (chained) SG table instead of chunk list. With this change the relevant code becomes clearer—no need for nested loops to build and use umem. Signed-off-by: Shachar Raindel Signed-off-by: Yishai Hadas Signed-off-by: Roland Dreier --- drivers/infiniband/core/umem.c | 120 +++++++++++++++++++---------------------- 1 file changed, 56 insertions(+), 64 deletions(-) (limited to 'drivers/infiniband/core') diff --git a/drivers/infiniband/core/umem.c b/drivers/infiniband/core/umem.c index a84112322071..a3a2e9c1639b 100644 --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -42,29 +42,29 @@ #include "uverbs.h" -#define IB_UMEM_MAX_PAGE_CHUNK \ - ((PAGE_SIZE - offsetof(struct ib_umem_chunk, page_list)) / \ - ((void *) &((struct ib_umem_chunk *) 0)->page_list[1] - \ - (void *) &((struct ib_umem_chunk *) 0)->page_list[0])) static void __ib_umem_release(struct ib_device *dev, struct ib_umem *umem, int dirty) { - struct ib_umem_chunk *chunk, *tmp; + struct scatterlist *sg; + struct page *page; int i; - list_for_each_entry_safe(chunk, tmp, &umem->chunk_list, list) { - ib_dma_unmap_sg(dev, chunk->page_list, - chunk->nents, DMA_BIDIRECTIONAL); - for (i = 0; i < chunk->nents; ++i) { - struct page *page = sg_page(&chunk->page_list[i]); + if (umem->nmap > 0) + ib_dma_unmap_sg(dev, umem->sg_head.sgl, + umem->nmap, + DMA_BIDIRECTIONAL); - if (umem->writable && dirty) - set_page_dirty_lock(page); - put_page(page); - } + for_each_sg(umem->sg_head.sgl, sg, umem->npages, i) { - kfree(chunk); + page = sg_page(sg); + if (umem->writable && dirty) + set_page_dirty_lock(page); + put_page(page); } + + sg_free_table(&umem->sg_head); + return; + } /** @@ -81,15 +81,15 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, struct ib_umem *umem; struct page **page_list; struct vm_area_struct **vma_list; - struct ib_umem_chunk *chunk; unsigned long locked; unsigned long lock_limit; unsigned long cur_base; unsigned long npages; int ret; - int off; int i; DEFINE_DMA_ATTRS(attrs); + struct scatterlist *sg, *sg_list_start; + int need_release = 0; if (dmasync) dma_set_attr(DMA_ATTR_WRITE_BARRIER, &attrs); @@ -97,7 +97,7 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, if (!can_do_mlock()) return ERR_PTR(-EPERM); - umem = kmalloc(sizeof *umem, GFP_KERNEL); + umem = kzalloc(sizeof *umem, GFP_KERNEL); if (!umem) return ERR_PTR(-ENOMEM); @@ -117,8 +117,6 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, /* We assume the memory is from hugetlb until proved otherwise */ umem->hugetlb = 1; - INIT_LIST_HEAD(&umem->chunk_list); - page_list = (struct page **) __get_free_page(GFP_KERNEL); if (!page_list) { kfree(umem); @@ -147,7 +145,18 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, cur_base = addr & PAGE_MASK; - ret = 0; + if (npages == 0) { + ret = -EINVAL; + goto out; + } + + ret = sg_alloc_table(&umem->sg_head, npages, GFP_KERNEL); + if (ret) + goto out; + + need_release = 1; + sg_list_start = umem->sg_head.sgl; + while (npages) { ret = get_user_pages(current, current->mm, cur_base, min_t(unsigned long, npages, @@ -157,54 +166,38 @@ struct ib_umem *ib_umem_get(struct ib_ucontext *context, unsigned long addr, if (ret < 0) goto out; + umem->npages += ret; cur_base += ret * PAGE_SIZE; npages -= ret; - off = 0; - - while (ret) { - chunk = kmalloc(sizeof *chunk + sizeof (struct scatterlist) * - min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK), - GFP_KERNEL); - if (!chunk) { - ret = -ENOMEM; - goto out; - } - - chunk->nents = min_t(int, ret, IB_UMEM_MAX_PAGE_CHUNK); - sg_init_table(chunk->page_list, chunk->nents); - for (i = 0; i < chunk->nents; ++i) { - if (vma_list && - !is_vm_hugetlb_page(vma_list[i + off])) - umem->hugetlb = 0; - sg_set_page(&chunk->page_list[i], page_list[i + off], PAGE_SIZE, 0); - } - - chunk->nmap = ib_dma_map_sg_attrs(context->device, - &chunk->page_list[0], - chunk->nents, - DMA_BIDIRECTIONAL, - &attrs); - if (chunk->nmap <= 0) { - for (i = 0; i < chunk->nents; ++i) - put_page(sg_page(&chunk->page_list[i])); - kfree(chunk); - - ret = -ENOMEM; - goto out; - } - - ret -= chunk->nents; - off += chunk->nents; - list_add_tail(&chunk->list, &umem->chunk_list); + for_each_sg(sg_list_start, sg, ret, i) { + if (vma_list && !is_vm_hugetlb_page(vma_list[i])) + umem->hugetlb = 0; + + sg_set_page(sg, page_list[i], PAGE_SIZE, 0); } - ret = 0; + /* preparing for next loop */ + sg_list_start = sg; } + umem->nmap = ib_dma_map_sg_attrs(context->device, + umem->sg_head.sgl, + umem->npages, + DMA_BIDIRECTIONAL, + &attrs); + + if (umem->nmap <= 0) { + ret = -ENOMEM; + goto out; + } + + ret = 0; + out: if (ret < 0) { - __ib_umem_release(context->device, umem, 0); + if (need_release) + __ib_umem_release(context->device, umem, 0); kfree(umem); } else current->mm->pinned_vm = locked; @@ -278,17 +271,16 @@ EXPORT_SYMBOL(ib_umem_release); int ib_umem_page_count(struct ib_umem *umem) { - struct ib_umem_chunk *chunk; int shift; int i; int n; + struct scatterlist *sg; shift = ilog2(umem->page_size); n = 0; - list_for_each_entry(chunk, &umem->chunk_list, list) - for (i = 0; i < chunk->nmap; ++i) - n += sg_dma_len(&chunk->page_list[i]) >> shift; + for_each_sg(umem->sg_head.sgl, sg, umem->nmap, i) + n += sg_dma_len(sg) >> shift; return n; } -- cgit v1.2.3-55-g7522